Question

What is the 22nd term of the arithmetic sequence where a1 = 8 and a9 = 56 ?

Answer 1

a9 = a+8b, right ? with b is difference 1st term and the next term
solve for b

Answer 2

ok i'm with you

Answer 3

what's do u get for b ?

Answer 4

142?

Answer 5

nopes
we know that the generally form to find term of the arithmetic sequence is an = a+(n-1)b
so if given a9=56 then
a1+(9-1)b = 56
8+8b=56, what's value of b here ?

Answer 6

an = a1+(n-1)b

Answer 7

150!

Answer 8

8+8b=56
8b=56-8
8b=48
b=48/8=6

Answer 9

158

Answer 10

next to find the 22nd term,
subtitite value a1=8, b=6, n=22 to formula above
an = a1+(n-1)b
a22 = 8+(22-1)6
a22 = 8+21(6)
a22 = 8+126
a22 = ?

Answer 11

134

Answer 12

that's right

Answer 13

for exercise for u, find the value of a50nd ?